Sign conventions for section forces Flashcards
What is the definition for bending moments?
The bending moments (B.M.) is the algebraic sum of the moments of the source about the section, taken on one side of the section
When we cut a beam, what are the two possibilities for the moment directions?
How are bending moments always draws?
Bending moments are always drawn on the tensile side of the beam. In a bending moment diagram, this means the sagging moments are drawn below the line (and are +ve) on the bottom of the M-diagram. Hogging moments are drawn above the line on the top of the M-diagram
What is a hogging moment?
What is a sagging moments?
What is the definition for shear force?
The shear force (S.F) at the section is the algebraic sum of the forces taken on one side of the section
When we cut a beam, what are the two possibilities for the shear force diagrams?
What is a positive shear force known as?
positive shear force is also known as clockwise shear and is drawn above the zero line
What is negative shear force known as?
counter-clockwise shear and is drawn below the zero line
What is the diagram for conventions for shear force?
